Abstract:

The characteristics of precipitation in Xilingol were studied to provide theories for the water exploit, flood prevention and drainage area management. According to the meteorological observation of 15 stations during the period of 1960-2009 in Xilingol, using statistical methods such as unitary linear regression (ULR), linear trend analysis and correlation analysis, the trend and temporal-spatial distribution of precipitation in the past 50 years were analyzed. The results showed that precipitation was unevenly distributed and widely varied among different areas, and exhibited a decreasing trend from southeast to northwest spatially. The yearly precipitation also showed an insignificant decreasing trend with a rate of -3.5 mm/10 a. The number of days with precipitation had a decreasing trend. Spring and winter precipitation showed an increasing trend, with a rate of 1.1 mm/10 a, and 0.1 mm/10 a, respectively. In summer and autumn, however, precipitation showed a decreasing trend, with a rate of -4.1 mm/10 a, and -0.7 mm/10 a, respectively. The decreasing trend in summer was the most significant.